Biological Activity, Hepatotoxicity, and Structure-Activity Relationship of Kavalactones and Flavokavins, the Two Main Bioactive Components in Kava (Piper methysticum)

Abstract

Kava (Piper methysticum Forst) is a popular and favorable edible medicinal herb which was traditionally used to prepare a nonfermented beverage with relaxant beneficial for both social and recreational purposes. Numerous studies conducted on kava have confirmed the presence of kavalactones and flavokawains, two major groups of bioactive ingredients, in this miraculous natural plant. Expectedly, both kavalactone and flavokawain components exhibited potent antianxiety and anticancer activities, and their structure-activity relationships were also revealed. However, dozens of clinical data revealed the hepatotoxicity effect which is indirectly or directly associated with kava consumption, and most of the evidence currently seems to point the compounds of flavokawains in kava were responsible. Therefore, our aim is to conduct a systematic review of kavalactones and flavokawains in kava including their biological activities, structure-activity relationships, and toxicities, and as a result of our systematic investigations, suggestions on kava and its compounds are supplied for future research.

Complementary and alternative medicine in patients with irritable bowel syndrome: A Pilot Study

“…(Piper methysticum) root is a perineal shrub and a member of the pepper family [26]. Various uses and pharmacological properties such as Anti-inflammatory activity, Anxiolytic activity, Sedative property, Antioxidant property, Antitumor activity and Immunomodulatory activity of the isolated kavalactones from the roots of kava have been reported [27]. Kava kava Ext.…”

Flavokawain C inhibits proliferation and migration of liver cancer cells through FAK/PI3K/AKT signaling pathway

“…Natural products have consistently been regarded as a crucial reservoir for novel drug discovery (Chopra et al 2021 ; Orhan 2022 ; Raslan 2022 ; Zhang et al 2022 ), particularly in the realm of anticancer drug development (Varghese et al 2021 ; Naeem et al 2022 ). Among these natural compounds, flavokawain derivatives have been documented to possess notable anticancer activities against a spectrum of cancer cells (Teschke et al 2011 ; Abu et al 2013 ; Wang et al 2021 ). Notably, flavokawain A and B have demonstrated significant anticancer efficacy across a range of malignancies including breast cancer (Abu et al 2015 , 2016 ), lung cancer (Hseu et al 2019 ; Li et al 2020 ), bladder cancer (Liu et al 2017 ), liver cancer (Pinner et al 2016 ), and melanoma (Hseu et al 2020a , b ).…”